Synchrotron-based x-ray fluorescence spectroscopy is a major scientific tool for solving a wide range of problems with important applications in the material and biological sciences. There is an urgent need for fast, efficient x-ray detectors for effective utilization of synchrotron-based facilities. The objective of this proposed work is to develop ZRG1 SSS6 (10) 2 1R43RR16820-01 JULY 12, 2001 WANG, Y. a silicon pixel-array detector (PAD) for synchrotron-based and laboratory-based x-ray applications. The PAD arrays will be bump bonded onto an application-specific integrated circuit (ASIC) which will provide high-energy-resolution and high-count-rate capability. Phase I will integrate an 8x8 array detector/IC module and demonstrate the potential performance of this approach. This will lay the foundation for the Phase II implementation of a PAD and the associated data acquisition system. The success of this project will lead to a new generation of detectors for high-count-rate x-ray applications. PROPOSED COMMERCIAL APPLICATIONS: The primary market will be the macromolecular biology facilities located at synchrotron radiation sources around the world. Additional applications are expected in the field of laboratory analytical instrumentation.